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Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

I have a 5x7 Premo Long Focus circa the late 1890's in very good condition except for the lens and shutter assembly which was a total loss. The lens that was on the camera was a Gundlach Opt. Co. but the original lens was probably a Baush & Lomb "Star" or "Victor" rectillinear lens (one of which I am looking for now). Now I intend to keep an original lens on the camera to stay true to authenticity but I would like to retrofit the camera with a better lens for more coverage. The camera is in perfect working order with light tight bellows (with 16-18 inches of extension!) and I've found that it has surprisingly more movement then I would have expected. I'd like to put a 210mm lens (capable of covering 5x7 with movements) on the camera to do some more movement oriented shooting (I will of course also shoot with an original lens if I can find one). The problem is that the lens board is only 2 3/4 inches x 2 3/4 inches and the hole for the lens is only 1 7/16 inches in diameter, far too small to fit a 210mm lens onto. I know that this particular camera is seen very rarely but the sister to it, the Premo Senior, is somewhat more common and I was hoping that someone out there has experimented with bigger lenses on these cameras and could offer some insight. I understand that I can enlarge the hole in the lens board (I'd prefer not to alter the original lens board) or make a new lens board with a bigger hole but are there any other options to get more bang out of this camera? Thanks in advance for your insight!

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

I have the reprint of the original Rochester Optical Co Catalogue from 1898. I'll find the original page that covers the long focus. It probably had a convertible lens. This is just up my street as I have his brother's Poco 8x10 long focus!

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

There was also a premo long focus special. This had more movements and came with a goerz series III (Dagor). They recommended that the rear element of the series III should be used by itself for longer shots!
There is separate info on the Victor etc. if you are interested?
I doubt whether many existing Victor shutters still work.

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

Thanks for uploading those. Very interesting to see. I agree that its unlikely to find a fully working original lens/ shutter assembly so what do you think might be a good solution to get it shooting again? Are there any lenses that would cover the cameras range of movements and fit the camera's lens board without modification? Any idea how many millimeters focal length the original lenses were. Just looking at the one that came with the camera (doesn't say a size), it barely looks bigger then a medium format lens (which gives me a hard time in understanding how it covered 5x7). Anyway, thanks again and I hope you have some ideas for me. I'd really love to use this camera and I already have four 5x7 film holders on the way haha.

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

On a page of the 1898 catalogue it also says that the Zeiss VIIa no.8 is also now available for the long focus premo. This would be excellent 3 focus "original choice". The single elements of the protar are better than the goerz dagor.
Premo 5x7 holders are no problem - even I have them!.
I would guess that the original dagor was either the 167mm or the 180mm. The combination of the no 8 Protar VIIa can be found on cameraeccentric's website.
The cheap RR would be symmetrical with only 2 posibilities.

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

Thanks for all of the information! I'll be thinking about the No. 8 Protar on Cameraeccentric's website but it doesn't look like it has a shutter unfortunately. You've helped me out a lot. Now I need to figure out what to do!

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

The Zeiss VIIa has probably supplied by B&L. The 1912 catalogue at cameraeccentric shows no. 8 as covering 5x7, with focal lengths 7 1/2, 113/4, 13 3/4". Could be supplied in a volute or Compound shutter.

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

Re: Modifying a 5x7 Premo Long Focus Lens Board for Better Lenses

Originally Posted by Ernest Purdum

I'm not as pessimistic as Mr. Tribe regarding the Victor. There really isn't all that much to go wrong with them. Dirty air cylinders are the most common problem.

Their main problem is their very construction. At higher speeds the air cylinders are not of use and the shutter relies on its spring. However, having no timing device (except the cylinders useless for those speeds) the spring itself is not enough to time the speed correctly.